There’s no single ingredient that is the culprit behind oxidation; rather, it has to do with how the oils and pigments react with your skin’s natural oils, acidity level and the humidity in the air.
Here a few ideas for how to stop a foundation from oxidizing:
Use a Primer
A primer will create a barrier between your skin and the foundation, which should help prevent it from reacting with your natural oils.
If you have combination skin, consider using an oil-controlling primer on your T-zone and a hydrating primer on the rest of your face.
Make up for ever has an amazing new line of primers. Their Mattifying primer would be great for your T-Zone, with the Nourishing primer on dry cheeks.
Blot Your Skin
After you apply your primer, take a half-ply of clean tissue and use it to blot your face. Do this again after applying your foundation—it will remove any excess oils and moisture to help the colour to stay true.
Set Your Makeup By Setting Powder
After you’ve applied your foundation, set it with a translucent setting powder. This will help lock the makeup in place and absorb any remaining oils that might trigger oxidation. You can also re-apply your setting powder throughout the day.
I think pure silica powder is the best way to go, as talc formulas can dry out the skin and look cakey, especially if you’re touching up with additional layers.
Set Your Makeup By Setting Spray
Another option is setting spray, which you mist all over your face as the last step in your makeup. Mac setting Spray works by lowering the temperature of your makeup to keep it looking freshly-applied.
Try Tinted Moisturizer
If you’re finding that most foundations oxidize on you, consider using tinted moisturizer, BB cream or CC cream instead. Since they’re not as pigmented, there’s less chance that the colour will change on you—plus, they’ll hydrate your dry skin at the same time.
If you’re worried that tinted moisturizer won’t provide enough coverage, so don’t worry it gives light to medium coverage as foundation.
Buy a Lighter Foundation Shade
If you’ve found a foundation formula you really love, it might be worth getting it one to two shades lighter so that when it oxidizes, you have a perfect match to your skin tone. This requires some trial and error, of course, and you’ll have to adjust your schedule to wait for the oxidation process to happen. However, it’s an option to consider if you can’t find anything that doesn’t change colour on you.
I hope that above few techniques can help you to prevent oxidation of foundation.